In manufacturing semiconductor devices, various processing apparatuses are used to subject a target substrate, such as a semiconductor wafer, to processes, such as CVD (Chemical Vapor Deposition), oxidation, diffusion, reformation, annealing, and etching. As processing apparatuses of this kind, vertical heat processing apparatuses that subject a number of wafers together to a heat process are known. In general, vertical heat processing apparatuses have a vertical airtight process chamber for accommodating wafers. The process chamber has a load port formed at the bottom, which is selectively opened and closed by a lid moved up and down by an elevator. Within the process chamber, the wafers are supported at intervals in the vertical direction on a holder called a wafer boat. A heating furnace is disposed around the process chamber.
There are vertical heat processing apparatuses of the type that has a blower for sending air into a heating furnace to forcibly air-cool a process chamber (for example, see Jpn. Pat. Appln. KOKAI Publication No. 2002-305189). When a heat process is finished, the blower is used to rapidly cool the wafers and process chamber.
On the other hand, there are heat processes using a low temperature range of, e.g., 100 to 500° C., such as a heat process for forming a low dielectric constant film on wafers. In such heat processes using a low temperature range, it is important to quickly increase the temperature and converge it to a predetermined heat process temperature. In this respect, it has been proposed to use a metallic process chamber in place of a quartz process chamber for a heat processing apparatus using a low temperature, so as to improve the thermal response of the heat processing apparatus.
However, for heat processes that generate sticky deposits, quartz process chambers are preferably used, because they are easy to clean or replace.
However, quartz process chambers have a large thermal capacity, and thus prolong the convergence time in attaining a target temperature in temperature increase recovery within a low temperature range.
Accordingly, they affect shortening of the TAT (Turn Around Time) and improvement of the throughput.